RSDL

The RESTful Service Description Language (RSDL) is a machine- and human-readable XML description of HTTP-based web applications (typically REST web services).

The language (defined by Michael Pasternak during his work on oVirt RESTful API) allows documenting the model of the resource(s) provided by a service, the relationships between them, and operations and the parameters that must be supplied for the operations. It specifies if parameters are mandated; and describes possible overloads as parameters sets.